Individual pairs of telephone circuit wires are frequently terminated in telephone company central offices, distribution cabinets and customer premise locations, for example, utilizing multi-terminal connector blocks, as is known in the art. Once terminated, these telephone circuit wires, usually comprised of cables containing narrow gauge insulated copper conductors, are grouped and then rerouted for appropriate distribution of the calls which they carry. Single connector blocks normally accommodate anywhere from 60 to 100 pairs of densely packed terminations, wherein multiple connector blocks are frequently contained in close proximity at a single location, e.g., one wall of a telephone switching room. Efficient utilization of mounting space is thus required since space within utility locations is traditionally at a premium.
Besides the incoming circuit terminations, the connector blocks are also utilized for making cross-connections between individual circuits on the connector blocks, as well as for mounting subsystems including test probes or current/voltage limiting circuit protectors which are used to prevent damage that may be caused by lightning, fallen power lines, or other external forces. For the most part, the terminations and cross-connections are made only at a front facing side of any connector block because the front area is the only area which is easily accessible. In addition, the circuit protection is also generally included at the front of the block, wherein grounding connections to establish a conduction path from the circuit protection to the mounting frame are required and accomplished, for example, by way of a ground bus connected to the mounting frame, such as the ground bus disclosed in U.S. Pat. No. 5,595,507 of Braun et al., assigned to the present assignee.
The many connections on the front face of a connector block make for a congested wiring arrangement. In order to energize a test probe or any active circuitry on a protector circuit, a power source must be made available at the connector blocks and provided to each such probe circuit. Complicating this issue is the fact that probes and protector circuits can be provided in pair-at-a-time or cartridge (multi-line) configurations.
Conventional protector circuits are passive insofar as they do not require a voltage source to drive their circuitry. Rather, such circuits react to over voltages or over currents in a given telephone line pair to affect a temporary disruption in service in response to a transient, or to permanently ground the line as a failsafe mode in response to a more extreme surge condition (e.g., by a lightning strike or dropped high-voltage power line).
In the event that the protector circuit is provided with an active component, such as an indicator as disclosed in co-pending U.S. patent application (Attorney Docket No. 1298/0E447), filed concurrently herewith for "PROTECTOR CIRCUIT WITH LED FAILSAFE INDICATOR," then a high potential signal must be provided to the circuit to drive its components. Such active circuitry requires a separate power supply and/or a high-voltage line to the connector block at the mounting bracket. In either case, additional wiring is required which is generally undesirable in an environment in which hundreds of telephone lines are typically brought together.
What is needed in the art and has heretofore not been available is a power bus provided within a conventional connector and, further, a Z-type connector which includes such a high-voltage power bus. What is also needed in the art, and has heretofore not been available, is a bus bar provided on a connector block mounting frame for energizing circuitry associated with the wires and cables at the mounting frame.